In a previous post we talked about TIG welding, whose acronym of the English word stands for (Tungsten Inert Gas). This type of welding is also known as GTAW from English (Gas Tungsten Arc Welding). On this and other topics, we recommend consulting the technical article on welding processes.
For the execution of the TIG welding A shielding gas must be used, which has the important function of protecting the bead in the process of solidification from oxidation, impurities and humidity found in the air. This with the aim of increasing the resistance of the weld to corrosion, promoting the appearance of pores and reducing the durability of the cord by changing the geometric characteristics of the joint. Additionally, this protection gas cools the welding gun or torch.
The shielding gas used in TIG welding is generally argon. Although mixtures of argon with a maximum of 2% hydrogen, helium or a mixture of argon and helium can also be used. These gases are packaged for use in tubes or cylinders, which are designed in compliance with international standards and the necessary specifications to be connected to the welding machine.
The tubes for TIG welding They are on the market in various presentations. These tubes, bottles or cylinders can be purchased in different sizes and with a wide variety of gas.
Types of TIG welding pipes
Depending on your storage capacity of gas, the tubes can be classified in tubes of 1/2, 1, 2, 3, 4 and 6 cubic meters and those of industrial capacity.
According to its durability, the tubes are classified as disposable or reusable. Disposable tubes generally have a small storage capacity and once their content is consumed, they must be replaced. Reusable cylinders are the most used by welding workers. These tubes can be recharged once their gas charge has been consumed, for which you must pay attention to the pressure in the tube. If the cylinder pressure is below 0.5 MPa, it is time to recharge the gas.
Depending on the type of gas they contain, the classification of welding tubes can be done as follows:
- Argon: This is the most recommended inert gas for TIG welding. It is suitable for working on any type of metal.
- Argon + Helium: this gas is recommended for working on stainless steels that are not compatible with argon, metals and alloys with a high level of thermal conductivity such as aluminum or copper. The addition of helium provides a faster welding job compared to argon alone.
- Argon + Hydrogen: this gas is indicated for manual or automatic welding of materials such as stainless steel, copper, nickel and their alloys.
These types of gases they are the most generic, currently on the market there is a great variety of these gases whose concentration of components varies, and they are used in higher specification works.
What welding tube to buy?
Taking into account the variety of existing tubes or cylinders, we must consider several factors to make the most appropriate selection.
The first thing to consider is the type of material on which the welding is going to be applied. Although argon is the most recommended gas for TIG welding, the other gas options are indicated to work with specific cases of materials.
The next factor to check is the time required to run the job in its entirety. In other words, how much time is required to weld. With this information, it is possible to determine the type of tube that is required, according to the gas storage capacity. The greater the amount of gas, the longer the welding time.
Another factor that can also influence the decision is the price. Argon is much cheaper than helium, so if helium is not specifically needed, it is more cost effective to use argon.
Safety factors of tubes for TIG welding
To work safely, several aspects must be taken into account when handling tubes for TIG welding.
- You must verify that the tube or cylinder does not present any damage, to avoid a possible explosion.
- The cylinder must be kept in a vertical position and attached to the base of the supports.
- Keep the tube in a sheltered place, where it cannot be damaged.
- You must not lift the welding machine if the gas tube is connected to it.
- Avoid making contact with an electrode on the cylinder.
- You must keep the tube away from the welding area and from electrical circuits that are not insulated.
- The gas tube must have a pressure reducer and a flow indicator.
- You must make sure to close the main valve of the gas tube, each time the welding work is completed.
- The gas tube must be connected to the rear of the welding machine, at the pressure reducer outlet only when the tube or cylinder has been given a location.
To close this article, we propose the video on How are tubes for welding made?